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Scala and the JVM · Part 8
I knew how to run sbt, but not how its build model worked. I built a small Scala 2.13 project and traced settings, tasks, scopes, Zinc, dependencies, Coursier and local publication back to the Maven concepts I already knew.
Scala and the JVM · Part 7
From one generator and an if guard to two lists and six combinations: I trace Scala for-comprehensions back to map, withFilter and flatMap, with runnable policy examples.
Scala and the JVM · Part 6
Three familiar operations, three different results. I explore Scala List with fictional insurance policies, compare it with Java streams, and reconnect find with Option.
Scala and the JVM · Part 5
Find a policy, find its email, and build a label. Understanding Scala 2 for-comprehensions by translating them into familiar flatMap and map calls, with all three optional outcomes made explicit.
Scala and the JVM · Part 4
Transform a value inside Option, then choose a fallback where it belongs. A walkthrough for Java developers of Scala 2 map, lambdas and getOrElse, derived from match and verified in a runnable lab.
Scala and the JVM · Part 3
From Java Optional to Scala Option: represent presence with Some, absence with None, and handle both outcomes with a match expression using our runnable policy lookup.
Scala and the JVM · Part 2
From a Java-style policy class to Scala 2 case classes: constructor properties, value equality versus identity, and copying data without changing the original.
Scala and the JVM · Part 1
Starting Scala 2 from Java and Spring: val and var, expressions, a first method, and a small sbt project you can run. The first step in the Scala/Play series.
Traces, Tempo and the LGTM stack
Wiring Spring Boot 4 + Spring Batch 6 to emit job/step traces into Tempo and spring_batch_* metrics into Prometheus — and the four config traps that each failed the same way: green build, zero errors, nothing exported.
I'm a Spring/Kafka backend engineer who could read Python but never wrote it. The AI world pulled me in, so I learned it by building a 10-lesson course that maps every concept back to Java, then built the tutor agent that taught me.